document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=877614>Question 877614</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A preschool playground has both bikes and trycicles. There is a total of 30 seats and 70 wheels how May bikes are there? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #529440 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=529440\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> There is 1 seat per bike/tricycle so  b+t = 30 ----> t = 30 - b\r<BR>\n" );
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document.write( "You have 70 wheels, which means\r<BR>\n" );
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document.write( "2b + 3t = 70\r<BR>\n" );
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document.write( "2b + 3(30 - b) = 70 ... plug in t = 30 - b\r<BR>\n" );
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document.write( "2b + 90 - 3b = 70\r<BR>\n" );
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document.write( "-b + 90 = 70\r<BR>\n" );
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document.write( "-b = 70 - 90\r<BR>\n" );
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document.write( "-b = -20\r<BR>\n" );
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document.write( "b = 20\r<BR>\n" );
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document.write( "There are 20 bikes.\r<BR>\n" );
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document.write( "To find the number of tricycles, plug b = 20 into t = 30 - b </SPAN>\n" );
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